Hunter 30T (1991) pump-out problem

Our H30T has encountered a pump out problem - using the lever pump, after a few strokes I encounter back pressure. I removed the vent hose from the through hull and it seems clear. Loosening the "squeaky beak valve" on the top of the vented loop shows air coming out when pumped. I then removed the hose that leads to the through hull and sprayed water in and it didn't fill up and the hose looked dry before I started so that is clear. I've pulled up the floor and exposed the Y fitting and am wondering what to do next. I presume the tank is full (although it sounds empty when tapped). I was thinking of running a domestic roto-rooter snakey thing down the inlet hose - maybe there is a blockage at the Y? I also need to replace the Jabsco pump toilet again (5 years old now) and the toilet outlet hose but am loathe to start on that while the tank is full!
All suggestions welcome.
Patrick, SW Florida

You removed the vent line from the thru-hull and checked the vent line...but did you check the vent thru-hull? Vent LINES rarely become blocked....the blockages are almost always in the vent thru-hull and the vent line connection to the tank--that end of the vent line and the vent fitting on the tank.
Use a screwdriver blade, ice pick--whatever works--to clean out the vent thru-hull. If there's a screen in it, knock it out...screens cause more problems than they prevent. You've already removed the vent line from the thru-hull...if the tank had been pressurized, you'd have wished you hadn't! But since we know it's not, it should be safe to remove the vent line from the tank. Scrape out whatever you find in the end of the hose and in the tank fitting. Put the vent line back on the tank and the thru-hull and you should be able to pump out. If not, there's a blockage in the tank discharge line, most likely in the connection to the tank.

I have removed the vent line from the through hull and inlet pipe from head. I can fill the vent hose with water and it doesn't drain into the tank so I assume the vent fitting on the tank is blocked. This is inaccessible unless I start cutting - I just noticed you refer to a Uniseal in another post. I can get to another part of the top of the tank - do I just drill a hole and fit (how?) one of these somehow as a new vent? In addition, with the inlet pipe open now, the pump is still straining against a blockage somewhere - looks like I need to replace the section between the Y and the tank. I'm about to replace the other hoses too - in your book you say use a double male barb on the old hose to pull the new through. What kind of cement on the barb pls?

None...the pipe fits tightly enough to seal completely without any.
You've asked enough questions that it'll be a lot easier to answer 'em if we can TALK instead of type...'cuz the answer to one question always creates two more questions. So if you'll send me a PM, I'll reply with email address so we can arrange a convenient time to spend 30-40 minutes on the phone and my phone number.

I think your boat is like ours (tank in the lav cabinet next to the toilet). If so, you will need to remove the wall next to the toilet to replace hoses anyway. It only takes 30 minutes or so and then you will have all the access you need. It will be tough replacing the hoses anyway due to the cramped spaces.

Also, Peggy is a treasure. Like many posters here we are lucky for her help.

I think maybe not - ours is 30T - tank (aluminium) is behind aft cabin bulkhead. My prob was twofold - the suction pipe to pump was badly corroded and blocked and the vent spigot on top of tank was completely blocked. Had to cut some access for that one. Fortunately, the inspection plate screws came off ok and I was able to do a temporary repair - cut off the corroded section of suction pipe (full of holes) and hose clamped on equivalent length of 1.5" white 148 hose. Changed head and hoses and will replace the tank in a few months when I have specced and ordered from Ronco. Will need to cut rear bulkhead access panel. My last challenge before resuming day sails is to replace the vent hose - the 3/4" white odor safe stuff won't quite go over the spigot end. I plan to heat it up and round off the end of the spigot and try again tomorrow. All this is just a holding solution to get us through the last bit of nice weather down here in FL.

Peggy - please don't worry! This is just a stop-gap measure so we can continue using the boat for a few more months There is quite a lead time on a new tank so I think this will get us through meanwhile. The boat really needs a new tank but it is completely inaccessible. It will be fine. The tip about pulling through new hoses with the double barb worked great thanks.

Based on what you've you've said here:My prob was twofold - the suction pipe to pump was badly corroded and blocked and the vent spigot on top of tank was completely blocked.
...there's little doubt that your aluminum tank is also so corroded inside that it's HIGHLY likely to leak if you use it. So instead of risking a smelly mess, pick up a portapotty at Walmart to use until the new tank from Ronco arrives...their cheapest ones are < $50.

I had this type of problem on my 1990 Hunter 30 last season. My problem was that some seaweed was sucked up into the raw water intake and made it all the way into the head pump assembly. I took the pump apart and cleaned it out, all was good after that. I too initially thought that I had overfilled the holding tank!